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 ***** BEGIN LICENSE BLOCK *****
 * Version: EPL 1.0/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Eclipse Public
 * License Version 1.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.eclipse.org/legal/epl-v10.html
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
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 * rights and limitations under the License.
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package org.jruby.compiler;

import java.util.List;
import java.util.Map;
import org.jcodings.Encoding;
import org.jruby.ast.NodeType;
import org.jruby.lexer.yacc.ISourcePosition;
import org.jruby.parser.StaticScope;
import org.jruby.util.ByteList;
import org.jruby.util.DefinedMessage;

/**
 *
 * @author headius
 */
public interface BodyCompiler {
    /**
     * End compilation for the method associated with the specified token. This should
     * close out all structures created for compilation of the method.
     * 
     * @param token A token identifying the method to be terminated.
     */
    public void endBody();
    
    /**
     * As code executes, values are assumed to be "generated", often by being pushed
     * on to some execution stack. Generally, these values are consumed by other
     * methods on the context, but occasionally a value must be "thrown out". This method
     * provides a way to discard the previous value generated by some other call(s).
     */
    public void consumeCurrentValue();
    
    /**
     * Push a copy the topmost value on the stack.
     */
    public void duplicateCurrentValue();
    
    /**
     * For logging, println the object reference currently atop the stack
     */
    public void aprintln();
    
    /**
     * Swap the top and second values on the stack.
     */
    public void swapValues();

    /**
     * Reverse the top n values on the stack.
     *
     * @param n The number of values to reverse.
     */
    public void reverseValues(int n);
    
    /**
     * This method provides a way to specify a line number for the current piece of code
     * being compiled. The compiler may use this information to create debugging
     * information in a bytecode-format-dependent way.
     * 
     * @param position The ISourcePosition information to use.
     */
    public void lineNumber(ISourcePosition position);
    
    public VariableCompiler getVariableCompiler();
    
    public InvocationCompiler getInvocationCompiler();
    
    /**
     * Retrieve the current "self" and put a reference on top of the stack.
     */
    public void retrieveSelf();
    
    /**
     * Retrieve the current "self" object's metaclass and put a reference on top of the stack
     */
    public void retrieveSelfClass();
    
    public void retrieveClassVariable(String name);
    
    public void assignClassVariable(String name);
    
    public void assignClassVariable(String name, CompilerCallback value);
    
    public void declareClassVariable(String name);
    
    public void declareClassVariable(String name, CompilerCallback value);
    
    /**
     * Generate a new "Fixnum" value.
     */
    public void createNewFixnum(long value);

    /**
     * Generate a new "Float" value.
     */
    public void createNewFloat(double value);

    /**
     * Generate a new "Bignum" value.
     */
    public void createNewBignum(java.math.BigInteger value);
    
    /**
     * Generate a new "String" value.
     */
    public void createNewString(ByteList value, int codeRange);

    /**
     * Generate a new dynamic "String" value.
     */
    public void createNewString(ArrayCallback callback, int count, Encoding encoding);
    public void createNewSymbol(ArrayCallback callback, int count, Encoding encoding);

    /**
     * Build a string using the given callback. A String will be create at the start,
     * and each iteration is expected to leave a String on the stack.
     */
    public void buildNewString(ArrayCallback callback, int count, Encoding encoding);

    /**
     * Append the given bytelist + coderange to the string currently on the stack.
     */
    public void appendByteList(ByteList value, int codeRange, boolean is19);

    /**
     * Append the object on stack to the string below it.
     */
    public void appendObject(boolean is19);

    /**
     * A "shortcut" append that skips conversions to String where possible.
     * Same stack requirements as appendObject.
     */
    public void shortcutAppend(boolean is19);

    /**
     * Convert a String on stack to a Symbol
     */
    public void stringToSymbol(boolean is19);

    /**
     * Generate a new "Symbol" value (or fetch the existing one).
     */
    public void createNewSymbol(String name);
    
    public void createObjectArray(Object[] elementArray, ArrayCallback callback);

    /**
     * Given an aggregated set of objects (likely created through a call to createObjectArray)
     * create a Ruby array object.
     */
    public void createNewArray(boolean lightweight);

    /**
     * Construct a Ruby array given an array of objects to feed to an ArrayCallback
     * to construct the elements of the array.
     *
     * @param sourceArray The objects that will be used to construct elements
     * @param callback The callback to which to pass the objects
     * @param lightweight Whether the array should be lightweight
     */
    public void createNewArray(Object[] sourceArray, ArrayCallback callback, boolean lightweight);

    /**
     * Construct a Ruby array given an array of objects to feed to an ArrayCallback
     * to construct the elements of the array. All the elements are guaranteed
     * to be literals, so the contents can safely be chunked if too large.
     *
     * @param sourceArray The objects that will be used to construct elements
     * @param callback The callback to which to pass the objects
     * @param lightweight Whether the array should be lightweight
     */
    public void createNewLiteralArray(Object[] sourceArray, ArrayCallback callback, boolean lightweight);

    /**
     * Create an empty Ruby array
     */
    public void createEmptyArray();
    
    /**
     * Create an empty Ruby Hash object and put a reference on top of the stack.
     */
    public void createEmptyHash();
    
    /**
     * Create a new hash by calling back to the specified ArrayCallback. It is expected that the keyCount
     * will be the actual count of key/value pairs, and the caller will handle passing an appropriate elements
     * collection in and dealing with the sequential indices passed to the callback.
     * 
     * @param elements An object holding the elements from which to create the Hash.
     * @param callback An ArrayCallback implementation to which the elements array and iteration counts
     * are passed in sequence.
     * @param keyCount the total count of key-value pairs to be constructed from the elements collection.
     */
    public void createNewHash(Object elements, ArrayCallback callback, int keyCount);

    /**
     * Create a new hash by calling back to the specified ArrayCallback. It is expected that the keyCount
     * will be the actual count of key/value pairs, and the caller will handle passing an appropriate elements
     * collection in and dealing with the sequential indices passed to the callback. This version expects
     * that all elements will be literals, and will break up the hash construction if it is too large.
     *
     * @param elements An object holding the elements from which to create the Hash.
     * @param callback An ArrayCallback implementation to which the elements array and iteration counts
     * are passed in sequence.
     * @param keyCount the total count of key-value pairs to be constructed from the elements collection.
     */
    public void createNewLiteralHash(Object elements, ArrayCallback callback, int keyCount);
    
    /**
    * @see createNewHash
    *
    * Create new hash running in ruby 1.9 compat version.
    */
    public void createNewHash19(Object elements, ArrayCallback callback, int keyCount);
    
    /**
     * Create a new range. It is expected that the stack will contain the end and begin values for the range as
     * its topmost and second topmost elements.
     * 
     * @param isExclusive Whether the range is exclusive or not (inclusive)
     */
    public void createNewRange(CompilerCallback beginEndCalback, boolean isExclusive);

    /**
     * Create a new literal lambda. The stack should contain a reference to the closure object.
     */
    public void createNewLambda(CompilerCallback closure);
    
    /**
     * Perform a boolean branch operation based on the Ruby "true" value of the top value
     * on the stack. If Ruby "true", invoke the true branch callback. Otherwise, invoke the false branch callback.
     * 
     * @param trueBranch The callback for generating code for the "true" condition
     * @param falseBranch The callback for generating code for the "false" condition
     */
    public void performBooleanBranch(BranchCallback trueBranch, BranchCallback falseBranch);
    
    /**
     * Perform a boolean branch operation based on the boolean top value
     * on the stack. If true, invoke the true branch callback. Otherwise, invoke the false branch callback.
     * 
     * @param trueBranch The callback for generating code for the "true" condition
     * @param falseBranch The callback for generating code for the "false" condition
     */
    public void performBooleanBranch2(BranchCallback trueBranch, BranchCallback falseBranch);
    
    /**
     * Perform a boolean branch operation based on the boolean global value
     * on the stack. If true, invoke the true branch callback. Otherwise, invoke the false branch callback.
     * 
     * @param trueBranch The callback for generating code for the "true" condition
     * @param falseBranch The callback for generating code for the "false" condition
     */
    public void performBooleanGlobalBranch(String globalName, BranchCallback trueBranch, BranchCallback falseBranch);
    
    /**
     * Perform a boolean branch operation based on the boolean constant value
     * on the stack. If true, invoke the true branch callback. Otherwise, invoke the false branch callback.
     * 
     * @param trueBranch The callback for generating code for the "true" condition
     * @param falseBranch The callback for generating code for the "false" condition
     */
    public void performBooleanConstantBranch(String globalName, BranchCallback trueBranch, BranchCallback falseBranch);
    
    /**
     * Perform a logical short-circuited Ruby "and" operation, using Ruby notions of true and false.
     * If the value on top of the stack is false, it remains and the branch is not executed. If it is true,
     * the top of the stack is replaced with the result of the branch.
     * 
     * @param longBranch The branch to execute if the "and" operation does not short-circuit.
     */
    public void performLogicalAnd(BranchCallback longBranch);
    
    
    /**
     * Perform a logical short-circuited Ruby "or" operation, using Ruby notions of true and false.
     * If the value on top of the stack is true, it remains and the branch is not executed. If it is false,
     * the top of the stack is replaced with the result of the branch.
     * 
     * @param longBranch The branch to execute if the "or" operation does not short-circuit.
     */
    public void performLogicalOr(BranchCallback longBranch);
    
    /**
     * Perform a boolean loop using the given condition-calculating branch and body branch. For
     * while loops, pass true for checkFirst. For statement-modifier while loops, pass false. For
     * unless loops, reverse the result of the condition after calculating it.
     * 
     * This version ensures the stack is maintained so while results can be used in any context.
     * 
     * @param condition The code to execute for calculating the loop condition. A Ruby true result will
     * cause the body to be executed again.
     * @param body The body to executed for the loop.
     * @param checkFirst whether to check the condition the first time through or not.
     */
    public void performBooleanLoopSafe(BranchCallback condition, BranchCallback body, boolean checkFirst);
    
    /**
     * Perform a boolean loop using the given condition-calculating branch and body branch. For
     * while loops, pass true for checkFirst. For statement-modifier while loops, pass false. For
     * unless loops, reverse the result of the condition after calculating it.
     * 
     * @param condition The code to execute for calculating the loop condition. A Ruby true result will
     * cause the body to be executed again.
     * @param body The body to executed for the loop.
     * @param checkFirst whether to check the condition the first time through or not.
     */
    public void performBooleanLoop(BranchCallback condition, BranchCallback body, boolean checkFirst);
    
    /**
     * Perform a boolean loop using the given condition-calculating branch and body branch. For
     * while loops, pass true for checkFirst. For statement-modifier while loops, pass false. For
     * unless loops, reverse the result of the condition after calculating it.
     * 
     * This version does not handle non-local flow control which can bubble out of
     * eval or closures, and only expects normal flow control to be used within
     * its body.
     * 
     * @param condition The code to execute for calculating the loop condition. A Ruby true result will
     * cause the body to be executed again.
     * @param body The body to executed for the loop.
     * @param checkFirst whether to check the condition the first time through or not.
     */
    public void performBooleanLoopLight(BranchCallback condition, BranchCallback body, boolean checkFirst);
    
    /**
     * Return the current value on the top of the stack, taking into consideration surrounding blocks.
     */
    public void performReturn();

    /**
     * Create a new closure (block) using the given lexical scope information, call arity, and
     * body generated by the body callback. The closure will capture containing scopes and related information.
     */
    public void createNewClosure(String file, int line, StaticScope scope, int arity, CompilerCallback body, CompilerCallback args, boolean hasMultipleArgsHead, NodeType argsNodeId, ASTInspector inspector);

    /**
     * Create a new closure (block) using the given lexical scope information, call arity, and
     * body generated by the body callback. The closure will capture containing scopes and related information.
     */
    public void createNewClosure19(String file, int line, StaticScope scope, int arity, CompilerCallback body, CompilerCallback args, boolean hasMultipleArgsHead, NodeType argsNodeId, String parameterList, ASTInspector inspector);
    
    /**
     * Create a new closure (block) for a for loop with the given call arity and
     * body generated by the body callback.
     */
    public void createNewForLoop(int arity, CompilerCallback body, CompilerCallback args, boolean hasMultipleArgsHead, NodeType argsNodeId, ASTInspector inspector);
    
    /**
     * Define a new method with the given name, arity, local variable count, and body callback.
     * This will create a new compiled method and bind it to the given name at this point in
     * the program's execution.
     */
    public void defineNewMethod(String name, int methodArity, StaticScope scope,
            CompilerCallback body, CompilerCallback args,
            CompilerCallback receiver, ASTInspector inspector, boolean root,
            String filename, int line, String parameterDesc);
    
    /**
     * Define an alias for a new name to an existing oldName'd method.
     */
    public void defineAlias(CompilerCallback args);

    /**
     * Assign a constant on the class or module currently in scope.
     *
     * @param name name of the constant
     * @param value callback to load the value
     */
    public void assignConstantInCurrent(String name, CompilerCallback value);

    /**
     * Assign a constant on a specific class or module.
     *
     * @param name name of the constant
     * @param moduleAndValue callback to load the class/module and value
     */
    public void assignConstantInModule(String name, CompilerCallback moduleAndValue);

    /**
     * Assign a constant on the Object class.
     *
     * @param name name of the constant
     * @param value callback to load the value
     */
    public void assignConstantInObject(String name, CompilerCallback value);

    /**
     * Assign a constant on the class or module currently in scope. The value
     * is expected to be on the top of the stack.
     *
     * @param name name of the constant
     */
    public void mAssignConstantInCurrent(String name);

    /**
     * Assign a constant on a specific class or module. The class/module
     * and value are expected to be on the top of the stack.
     *
     * @param name name of the constant
     */
    public void mAssignConstantInModule(String name);

    /**
     * Assign a constant on the Object class. The value
     * is expected to be on the top of the stack.
     *
     * @param name name of the constant
     */
    public void mAssignConstantInObject(String name);
    
    /**
     * Retrieve the constant with the specified name available at the current point in the
     * program's execution.
     * 
     * @param name The name of the constant
     */
    public void retrieveConstant(String name);

    /**
     * Retreive a named constant from the RubyModule/RubyClass that's just been pushed.
     * 
     * @param name The name of the constant
     */
    public void retrieveConstantFromModule(String name);

    /**
     * Retreive a named constant from the RubyModule/RubyClass that's just been pushed.
     *
     * @param name The name of the constant
     */
    public void retrieveConstantFromObject(String name);
    
    /**
     * Load a Ruby "false" value on top of the stack.
     */
    public void loadFalse();
    
    /**
     * Load a Ruby "true" value on top of the stack.
     */
    public void loadTrue();
    
    /**
     * Load a Ruby "nil" value on top of the stack.
     */
    public void loadNil();
    
    public void loadNull();
    
    /**
     * Load the Object class
     */
    public void loadObject();
    
    /**
     * Retrieve the instance variable with the given name, based on the current "self".
     * 
     * @param name The name of the instance variable to retrieve.
     */
    public void retrieveInstanceVariable(String name);
    
    /**
     * Assign the value on top of the stack to the instance variable with the specified name
     * on the current "self". The value is consumed.
     * 
     * @param name The name of the value to assign.
     */
    public void assignInstanceVariable(String name);
    
    /**
     * Assign the value on top of the stack to the instance variable with the specified name
     * on the current "self". The value is consumed.
     * 
     * @param name The name of the value to assign.
     * @param value A callback for compiling the value to assign
     */
    public void assignInstanceVariable(String name, CompilerCallback value);
    
    /**
     * Assign the top of the stack to the global variable with the specified name.
     * 
     * @param name The name of the global variable.
     */
    public void assignGlobalVariable(String name);
    
    /**
     * Assign the top of the stack to the global variable with the specified name.
     * 
     * @param name The name of the global variable.
     * @param value The callback to compile the value to assign
     */
    public void assignGlobalVariable(String name, CompilerCallback value);
    
    /**
     * Retrieve the global variable with the specified name to the top of the stack.
     * 
     * @param name The name of the global variable.
     */
    public void retrieveGlobalVariable(String name);
    
    /**
     * Perform a logical Ruby "not" operation on the value on top of the stack, leaving the
     * negated result.
     */
    public void negateCurrentValue();
    
    /**
     * Convert the current value into a "splatted value" suitable for passing as
     * method arguments or disassembling into multiple variables.
     */
    public void splatCurrentValue(String methodName);
    
    /**
     * Given a splatted value, extract a single value. If no splat or length is
     * zero, use nil
     */
    public void singlifySplattedValue();

    /**
     * 1.9 version of singlifySplattedValue.
     */
    public void singlifySplattedValue19();
    
    /**
     * Given an IRubyObject[] on the stack (or otherwise available as the present object)
     * call back to the provided ArrayCallback 'callback' for 'count' elements, starting with 'start'.
     * Each call to callback will have a value from the input array on the stack; once the items are exhausted,
     * the code in nilCallback will be invoked *with no value on the stack*.
     */
    public void forEachInValueArray(int count, int start, Object source, ArrayCallback callback, CompilerCallback argsCallback);

    /**
     * Given an IRubyObject[] on the stack (or otherwise available as the present object)
     * call back to the provided ArrayCallback 'callback' for 'count' elements, starting with 'start'.
     * Each call to callback will have a value from the input array on the stack; once the items are exhausted,
     * the code in nilCallback will be invoked *with no value on the stack*.
     */
    public void forEachInValueArray(int count, int preSize, Object preSource, int postSize, Object postSource, ArrayCallback callback, CompilerCallback argsCallback);
    
    /**
     * Ensures that the present value is an IRubyObject[] by wrapping it with one if it is not.
     */
    public void ensureRubyArray();
    
    /**
     * Ensures that the present value is an IRubyObject[] by wrapping it with one or coercing it if it is not.
     */
    public void ensureMultipleAssignableRubyArray(boolean masgnHasHead);
    
    public void issueBreakEvent(CompilerCallback value);
    
    public void issueNextEvent(CompilerCallback value);
    
    public void issueRedoEvent();
    
    public void issueRetryEvent();

    public void asString();

    public void nthRef(int match);

    public void match(boolean is19);

    public void match2(CompilerCallback value, boolean is19);

    public void match2Capture(CompilerCallback value, int[] scopeOffsets, boolean is19);

    public void match3(boolean is19);

    public void createNewRegexp(ByteList value, int options);
    public void createNewRegexp(CompilerCallback createStringCallback, int options);
    public void createDRegexp19(ArrayCallback arrayCallback, Object[] sourceArray, int options);
    
    public void pollThreadEvents();

    public void literal(String value);

    /**
     * Push the current back reference
     */
    public void backref();
    /**
     * Call a static helper method on RubyRegexp with the current backref 
     */
    public void backrefMethod(String methodName);
    
    public void nullToNil();

    /**
     * Makes sure that the code in protectedCode will always run after regularCode.
     */
    public void protect(BranchCallback regularCode, BranchCallback protectedCode, Class ret);
    public void rescue(BranchCallback regularCode, Class exception, BranchCallback protectedCode, Class ret);
    public void performRescue(BranchCallback regularCode, BranchCallback rubyCatchCode, BranchCallback rubyElseCode, boolean needsRetry);
    public void performRescueLight(BranchCallback regularCode, BranchCallback rubyCatchCode, BranchCallback rubyElseCode, boolean needsRetry);
    public void performEnsure(BranchCallback regularCode, BranchCallback ensuredCode);
    public void stringOrNil();
    public void pushNull();
    public void pushString(String strVal);
    public void pushByteList(ByteList bl);
    public void pushDefinedMessage(DefinedMessage definedMessage);
    public void isMethodBound(String name, BranchCallback trueBranch, BranchCallback falseBranch);
    public void hasBlock(BranchCallback trueBranch, BranchCallback falseBranch);
    public void isGlobalDefined(String name, BranchCallback trueBranch, BranchCallback falseBranch);
    public void isConstantDefined(String name);
    public void isInstanceVariableDefined(String name);
    public void isClassVarDefined(String name, BranchCallback trueBranch, BranchCallback falseBranch);
    public Object getNewEnding();
    public void ifNull(Object gotoToken);
    public void isNil(BranchCallback trueBranch, BranchCallback falseBranch);
    public void isNull(BranchCallback trueBranch, BranchCallback falseBranch);
    public void ifNotNull(Object gotoToken);
    public void setEnding(Object endingToken);
    public void go(Object gotoToken);
    public void isConstantBranch(BranchCallback setup, String name);
    public void metaclass();
    public void getVisibilityFor(String name);
    public void isPrivate(Object gotoToken, int toConsume);
    public void isNotProtected(Object gotoToken, int toConsume);
    public void selfIsKindOf(Object gotoToken);
    public void loadCurrentModule();
    public void notIsModuleAndClassVarDefined(String name, Object gotoToken);
    public void loadSelf();
    public void ifSingleton(Object gotoToken);
    public void getInstanceVariable(String name);
    public void getFrameName();
    public void getFrameKlazz(); 
    public void superClass();
    public void attached();    
    public void ifNotSuperMethodBound(Object token);
    public void isInstanceOf(Class clazz, BranchCallback trueBranch, BranchCallback falseBranch);
    public void isCaptured(int number, BranchCallback trueBranch, BranchCallback falseBranch);
    public void concatArrays();
    public void appendToArray();
    public void argsCatToArguments();
    public void argsCatToArguments19();
    public void splatToArguments();
    public void splatToArguments19();
    public void convertToJavaArray();
    public void aryToAry();
    public void toJavaString();
    public void aliasGlobal(String newName, String oldName);
    public void undefMethod(CompilerCallback nameArg);
    public void defineClass(String name, StaticScope staticScope, CompilerCallback superCallback, CompilerCallback pathCallback, CompilerCallback bodyCallback, CompilerCallback receiverCallback, ASTInspector inspector);
    public void defineModule(String name, StaticScope staticScope, CompilerCallback pathCallback, CompilerCallback bodyCallback, ASTInspector inspector);
    public void unwrapPassedBlock();
    public void performBackref(char type);
    public void callZSuper(CompilerCallback closure);
    public void appendToObjectArray();
    public void checkIsExceptionHandled(ArgumentsCallback rescueArgs);
    public void rethrowException();
    public void loadClass(String name);
    public void loadStandardError();
    public void unwrapRaiseException();
    public void loadException();
    public void setFilePosition(ISourcePosition position);
    public void setLinePosition(ISourcePosition position);
    public void checkWhenWithSplat();
    public void createNewEndBlock(CompilerCallback body);
    public void runBeginBlock(StaticScope scope, CompilerCallback body);
    public void rethrowIfSystemExit();

    public BodyCompiler chainToMethod(String name);
    public BodyCompiler outline(String methodName);
    public void wrapJavaException();
    public void literalSwitch(int[] caseInts, Object[] caseBodies, ArrayCallback casesCallback, CompilerCallback defaultCallback);
    public void typeCheckBranch(Class type, BranchCallback trueCallback, BranchCallback falseCallback);
    public void loadFilename();

    /**
     * Store the current live exception object in the $! thread-global.
     */
    public void storeExceptionInErrorInfo();

    /**
     * Store the current exception in $!, wrapping in NativeException if necessary.
     */
    public void storeNativeExceptionInErrorInfo();

    public void clearErrorInfo();

    public void compileSequencedConditional(
            CompilerCallback inputValue,
            FastSwitchType fastSwitchType,
            Map<CompilerCallback, int[]> switchCases,
            List<ArgumentsCallback> conditionals,
            List<CompilerCallback> bodies,
            CompilerCallback fallback);

    public void raiseTypeError(String string);

    public void traceLine();
    public void traceClass();
    public void traceEnd();

    public String getNativeMethodName();

    public void preMultiAssign(int head, boolean args);

    /**
     * Return true if this method compiled is a "simple" root compiler, i.e.
     * not chained and not a block/closure.
     * 
     * @return
     */
    public boolean isSimpleRoot();

    /**
     * Pass two stack elements, the first an array, to the "argsPush" utility method.
     */
    public void argsPush();

    /**
     * Pass two stack elements, converting the first to an array, to the "argsCat" utility method.
     */
    public void argsCat();

    /**
     * Load the specified encoding.
     */
    public void loadEncoding(Encoding encoding);

    /**
     * Check defined?() for a Call
     * @stack: target receiver object
     */
    public void definedCall(String name);

    /**
     * Check defined?() for a Not. Under 1.9, returns "method" if the contained
     * logic evaluates ok.
     * 
     * @stack: String defined for contained expression
     */
    public void definedNot();
    
    /**
     * Convert the top IRubyObject value on the stack to a primitive boolean
     * using IRubyObject.isTrue();
     */
    public void isTrue();
}
